As an important technology in the Internet of things, RFID has attracted extensive attention and research in recent years because of its low cost, security and high efficiency. This paper presents an intelligent vehicle management system based on UHF RFID (Internet of vehicles). The system is composed of RFID hardware system, CDMA system, GIA system and data processing system. It can realize the intelligent identification, positioning, tracking, speed measurement, monitoring and management of vehicles, so as to solve the current severe problems such as road congestion, vehicle overspeed and overload, vehicle theft and official vehicle management.
With the development of economy and technology, China’s residents’ car ownership has increased year by year. The sharp increase of vehicles has brought severe challenges to today’s vehicle management: Vehicle congestion, vehicle theft, difficult vehicle identification, and frequent traffic accidents caused by speeding. How to use scientific and technological means to make effective use of road resources and maintain smooth roads; Clarify the identity of vehicles so that the unit can effectively manage the entry and exit of vehicles; Curb vehicle overspeed and overload and ensure vehicle driving safety; Improve the “self-defense” level of vehicles to prevent vehicle theft; Transparent identity information of official vehicles and restrict the private use of official vehicles? In this paper, an intelligent vehicle management system based on UHF RFID, GSM and GIA is proposed to solve the above problems. The second part of this paper describes the intelligent vehicle management system to identify the identity of incoming and outgoing vehicles in the closed university campus, so as to strengthen the management of incoming and outgoing vehicles. The third part describes that the intelligent vehicle management system collects the road information in real time in the open road network, so as to facilitate the transportation department to optimize the traffic flow and reasonably allocate the road resources; And carry out positioning, speed measurement, tracking and identity information reading for dangerous vehicles. The fourth part, combined with the current situation of replacing new military license plates in the whole army and armed police forces, puts forward the idea of replacing new RFID intelligent license plates and using the intelligent vehicle management system, and expounds the solution of the system to the current vehicle management problems.
1. Vehicle identification and management subsystem applied to closed areas
The university is a relatively open environment. The complexity of vehicles in the university area and the dispersion of vehicle management have brought hidden dangers to the life and property safety of university teachers and students. In particular, the “my father is Li Gang incident” that shocked Chinese people occurred in Hebei University in 2010 has led to the rectification of campus order and the strengthening of the management of vehicles entering, leaving and parking on the campus, It is particularly important to protect the life and property safety of teachers and students.
1.1 status of vehicle identification system
At present, the vehicle management of some universities adopts manual discrimination: that is, the school issues paper signboards to the vehicles of the unit, the guard identifies whether the incoming and outgoing vehicles belong to the unit, and foreign vehicles go through temporary visit procedures at the designated place. This method not only has low efficiency and long inspection delay, but also buries hidden dangers for forging signboards because it does not adopt technical means to prevent counterfeiting.
Another part of universities adopt an inductive IC card access management system. Although this card has the characteristics of security and confidentiality, not easy to be imitated, easy to carry and durable, this traditional IC card itself is a short-range sensing card, and the reading distance is only a few centimeters. In actual use, the owner needs to stop the vehicle, roll down the window, hold the IC card out of the window, swipe the card, and then continue to go in and out. Compared with the previous management system, this vehicle access management system takes longer time during the inspection and does not bring convenience to the owner, especially in rainy and snowy weather, hot weather and other climates; IC card vehicle access management system essentially needs parking, and can not achieve more advanced and humanized barrier free automatic access.
1.2 system composition
The vehicle management system is mainly composed of RFID hardware (active RFID smart license plate, long-distance reader, channel controller, road gate), image capture module, computer and software management system.
1.3 working principle
The system adopts UHF long-distance RFID technology, and each vehicle is equipped with an active RFID smart license plate registered in the vehicle access system in advance.
RFID the license plate stores information including vehicle department, license plate number, driver’s name and ID number. The active RFID license plate will continuously transmit UHF signals. When the remote reader installed near the entrance and exit receives the signal, the remote card reader will send the card signal to the channel controller through 485 (or Wigan) interface. The channel controller judges the legitimacy of the license plate. If it is legal, the relay on the controller drives the gate to open to allow vehicles to enter and exit, otherwise it will not be released. Since there is no special license plate for foreign vehicles, the intelligent gate controller does not receive information and generates an interrupt signal after the vehicle enters the active recognition area. At this time, the intelligent gate controller sends a warning command, the voice equipment prompts the driver to stop, registers at the guard, and automatically starts the camera to capture the valid information of the vehicle (license plate number). At this time, the driver needs to cooperate with the guard to register in the guard room, and then the guard operates the intelligent gate controller to open the gate through the wireless remote control device. The guard room at each gate of the campus is used as the system sub control point, and the computer records the vehicle access records in real time, including the access time, vehicle department and owner information.
1.4 system characteristics
The main features of the vehicle management system are as follows:
(1) Long distance: the reading distance can be easily realized within 10m. Due to the actual requirements of vehicle access control, the card reading distance should not be too long. This scheme does not need to manually close to the card swiping or pass through the designated area to realize full-automatic recognition, which can avoid the problem that the driver must swing the window close to the reader to swipe the card in bad weather. Therefore, it can effectively alleviate the congestion caused by too many vehicles in and out of the warehouse and queuing to swipe the card in peak hours.
(2) Stable operation: the reading distance of the long-distance reader is stable and not easy to be affected by the surrounding environment. Active RFID can effectively break through the shielding effect of automobile explosion-proof metal mesh and smoothly exchange data with readers.
(3) High reliability: it can operate normally within the ambient temperature of – 40 ~ 85 ℃, especially under the low temperature in the north and high temperature in the south, and can effectively resist dust and pollutants in the air.
(4) High anti-interference: there are no special requirements for various interference sources on site, and the installation is convenient and simple.
(5) Ultra low power consumption: long service life, low average cost, safe and healthier to human body, no radiation damage.
(6) Anti collision: Advanced anti-collision technology can identify hundreds of labels at the same time per second.
2 vehicle positioning and speed measurement subsystem applied to open road network
2.1 demand analysis
With the development of economy and automobile technology, there are more and more residents with cars, and the traffic jam is becoming more and more serious. Traffic jam not only wastes everyone’s valuable time, but also makes traffic accidents occur frequently. How to make full use of road network, shorten vehicle running time, reduce driving delay, ensure driving safety and improve road capacity has become an important issue to be solved in each city.
In addition, with the continuous expansion of enterprise scale and performance, the number of vehicles required for distribution and operation is gradually increasing. The risk control, overspeed control, regional alarm and other related functions of private work, private affairs and outgoing vehicles have attracted more and more attention of enterprise managers.
On this basis, the subsystem of intelligent vehicle management system – vehicle positioning and speed measurement system – came into being.
2.2 current situation and comparison of vehicle positioning
In the current vehicle positioning system, the typical vehicle position information acquisition method is vehicle positioning based on GPS global positioning system and acceleration sensor.
This is a positioning method based on mobile station, that is, the on-board positioning device provides location information to the vehicle, and then the vehicle reports the obtained location information to the vehicle management system through wireless communication. This method of actively sending location information by the located object has the disadvantages of occupying more communication resources and high system operation cost, and there may be temporary positioning blind spots in urban high-rise areas, under viaducts, boulevards and tunnels.
2.3 system composition
The system is mainly composed of vehicles equipped with RFID smart license plates, data wireless transceiver nodes (RFID remote Readers), CDMA modules, GIA systems, data processing units, data processing and control centers. Fig. 1 is a schematic diagram of a vehicle positioning and speed measurement system.
2.4 system operation principle
The system obtains the identity information of the vehicle based on the method of reading RFID electronic tag, obtains the position information of the vehicle by using the multi base station wireless positioning method based on toda, and obtains the speed information of the vehicle by processing the Doppler frequency shift generated by the vehicle movement. Each RFID license plate stores the license plate number, vehicle usage, maximum load, maximum carrying capacity, owner name and ID number of the vehicle. According to the building characteristics and traffic flow in different regions, a certain number of data wireless transceiver nodes are installed in order to maximize the utilization of resources and reduce the waste of node layout. Each data wireless transceiver node directionally sends the coded and modulated command signal according to a certain frequency. The RFID smart license plate within the coverage of the node receives this command and is authenticated. If it is correct, it will send its own uid according to the requirements of the command. The data wireless transceiver node receives this information, demodulates and decodes it to obtain the vehicle identity information, It is sent to the data processing unit through the CDMA module, and then sent to the urban data processing and control center by the data processing unit. The method based on multi base station wireless positioning is that the wireless data transceiver node actively obtains the vehicle position information and uses the received signal strength (RSSI), time of arrival (TOA) and time difference of arrival (TDOA) to locate. In the first step, the robust estimation method is used to reduce its impact on the estimated value.
On the basis of the first step estimation, three data wireless transceiver nodes closest to the RFID smart license plate are found, and the TDOA values of these three nodes are used for the second positioning, so as to obtain the vehicle position information and transmit it to the data processing and control center. The data processing and control center can roughly describe the running track of the vehicle according to the obtained information. Through real-time estimation of Doppler frequency shift caused by vehicle movement, data processing can measure the speed of the vehicle in real time.
3 application prospect
Recently, the whole army and the armed police force have uniformly used the new military vehicle number plate since May 1, 2013. This time, the number plates of new military vehicles will be replaced, focusing on the implementation of “anti-counterfeiting, anti abuse, anti random hanging, anti loss and anti-theft”. We made full use of information technology, strictly controlled the whole process and all-round control of license approval, issuance and use, improved the joint military local work and assistance mechanism, strengthened the crackdown on the manufacture, trafficking and use of fake military vehicle license plates, and fundamentally solved the prominent problems existing in military vehicle management.
If we comply with the current trend of military license plate replacement and the transportation department upgrades the national license plates and replaces them with intelligent license plates based on RFID, we can effectively curb and solve the problems of vehicle speeding, car theft crime and official vehicle management.
At present, the traffic police department mainly restricts the drivers’ speeding behavior by placing speedometers in some uncertain places, capturing speeding vehicles and punishing them accordingly. However, the few speedometers have small monitoring strength and scope, which can not fundamentally touch the drivers’ fluke psychology. If the national license plates are replaced with RFID based smart license plates, and data wireless transceiver nodes are installed in each road section, any vehicle will be in the omnipresent speed measurement network of all-weather and all regions. The advanced technology and speed measurement network without dead corner and blind area fundamentally standardize and eliminate the driver’s fluke psychology, so as to guide the driver to abide by the traffic rules.
3.2 car theft crime
In recent years, with the rapid development of economy, the number of cars has also increased rapidly. Therefore, cars have attracted the “attention” of criminals, and the crime of car theft is becoming more and more rampant, and its criminal means are becoming more and more sophisticated. The crime of car theft damages the property interests of the state and the people. How to improve technology and not give thieves an opportunity? For such criminal incidents, in addition to assembling smart license plates, electronic labels need to be attached inside the car engine as an auxiliary tool for vehicle recognition. If the thief does not damage the smart license plate after stealing the car, the vehicle will be under real-time monitoring, and the public security department can catch it by accurately locating the vehicle. If the thief is more “smart”, after stealing the vehicle, he damages the smart license plate and thinks he can escape the law. At this time, the electronic tag attached to the engine will play a role as an auxiliary tool for vehicle identification. Its function is the same as that of the electronic tag on the smart license plate. The stolen vehicle is still under real-time monitoring, and the engine will not work normally when it is damaged due to the special structure and attachment position of the auxiliary electronic tag. After the adoption of this technology, no matter where the thief transports the car, he can’t escape the monitoring of the public security department and the law.
3.3 official vehicles
The current bus problem is mainly the serious phenomenon of private use of buses . For a long time, the phenomenon of bus tourism and bus transportation of children to and from school has occurred from time to time, which not only corrupt the social atmosphere, damage the self-image of Party and government organs and cadres, but also cause losses to the country and have a negative impact on the masses. Replacing the new license plate can provide convenience for Discipline Inspection and supervision personnel to investigate and deal with buses. Part of the information storage area of the new RFID license plate is used to store the global unique identifier (uid), and the rest can store 512 B ~ 4 MB of information. When replacing a new license plate for an official vehicle, in addition to the basic identity information, the license plate can also record the vehicle category (official vehicle), work unit and other information.
The discipline inspection department can place RFID readers around tourist areas, hotels and other entertainment places, and the reading distance can be adjusted to 3 km. When some civil servants who violate discipline drive buses to consume here, their bus information will be recorded and transmitted wirelessly to the data processing center of the discipline inspection department through CDMA to provide evidence for law enforcement of the discipline inspection department. This method can effectively restrict the private use of buses.
This paper proposes an intelligent vehicle management system based on RFID, and expounds the strong support for the construction of identity recognition and management subsystem applied to closed areas such as universities and positioning and speed measurement subsystem applied to open road network according to the needs of different environments. The system uses Internet of things technology to solve the problems of multi station data unification and multi station integrated management, and realizes the functions of multi station real-time monitoring, intelligent alarm and automatic patrol inspection, which provides a practical reference for the implementation of regulation integrated management mode. The system has passed the relevant qualification test of China Electric Power Research Institute. The test results show that based on the engineering practice, the system has realized the expected functions on the premise of meeting the substation communication protocol, with advanced architecture, good security, high reliability, strong compatibility and flexible control of the number of substations.
Responsible editor: CT